Interesting Question, any Answer?
 

From where do we derive the word “roger” as a response implying that a message has been received and understood?

Ok- I'm the trivia princess and can actually answer this.

Roger was chosen for radio transmission to represent the letter R (r = received)during radio conversations, (like Delta represents D and Charlie represents C, etc) R was chosen because it was the word in the phonetic alphabet that stood for the letter R. The military started using the word during WWII. It was taken from the proper name "Roger", but there was never a pilot named "Roger Wilco"

bonus trivia: After the phonetic alphabet used by the military was changed, (after the Korean war), Romeo took the place of Roger.

ZA

It should also be noted that “roger” does not and never has meant that a message has been received and understood, merely received — an important difference. To establish that the content has been correctly interpreted a message needs to be “read back” to the sender, who will then confirm its accuracy

LOL, I remember that from Tails on Sonic's Adventure. Now it makes sense.

If anyone is curious (not to be confused with Curiouss! haha) the military phonetic alphabet is as follows*:

Alpha
Bravo
Charlie
Delta
Echo
Foxtrot
Gulf
Hotel
India
Juliet
Kilo
Lima
Mike
November
Oscar
Papa
Quebec
Romeo
Sierra
Tango
Uniform
Victor
Whiskey
X-ray
Yankee
Zulu

*Courtesy of CDR KillarneyRose

So when they want someone to SEND HELP do they radio:
Sierra Echo November Delta Hotel Echo Lima Papa?

I'm just curious what the purpose of the alphabet is (ie: I KNOW NOTHING)

No Hootie, they would just radio "send help" :)

They use the phonetic alphabet whenever they need to spell something out. It's spoken, not written. For example, in the Navy there is an airplane called an "E-2" and one called a "C-2". Since E and C are similar sounding, to avoid confusion the person on the radio would refer to one as an "Echo - 2" and one as a "Charlie - 2".

Basically, the phonetic alphabet is just a precaution to make sure that letters aren't mistaken for other letters.

Plus, it sounds cool! lol :D

Gulf should be Golf

Thanks, Rob! My bad

"Roger Wilco" means "Recieved, Will Comply"